Liquid developer tray and feed assembly



Jim 1967 JEAN-PAUL R. AUBlN 3,301,160

.LIQUID DEVELOPER TRAY AND FEED ASSEMBLY Filed Dec 19, 1963 I INVENTOR,

BIN

JEAN" PAUL R AU Z131 United States Patent C) M Thisinvention pertains toan improvement in liquid developer trays. developer trays employed inthe developing of moist diazotype materials. 1 However, the inventionhas application also to developer trays and the like which are used forother purposes, and to liquid containers-and dispensing devices ingeneral.

In the document copying art, and particularly in themoist diazotypeprocesses, it is'highly desirable to have a uniformly fresh or freshlyreplenished solution-at all times at all points in the apparatus.Various attempts have been made in the past to supply fresh solution tophotographic developer trays, tanks, etc. Thus attempts have been madeto replenish the solution, for example, by establishing a multiplicityof supply points so that fresh liquid can come from multiple sources.Efforts also have been made to assure uniform quality, homogeneity andfreshness, etc., throughout the system by pumping the developer liquidcontinuously in a circulating manner. Such arrangements or procedures,while having certain merits, tend to result in unduly complex andexpensive equipment which frequently is not justified. Moreover, theymay tend to requirela-rger inventories of liquid developer;Whilereference has been made above to developer, similar comments applyto fixing solutions, etc.

It is an object of the present invention to provide a liquid supplytray, i.e., a developer tray for photocopying purposes, which comprisesa plurality of developer compartments and is equipped with a simpleconduit means for supplying fluid simultaneously from a single point tothe plural compartments in such a way as to maintain homogeneity ofliquid, with suitable freshness and a minimum of spent solutionconsistent with the rate of liquid consumption throughout essentiallyall points in the system.

A further object is to provide a developer tray having a plurality ofelongated parallel troughs, each of which It has particularapplicationto liquid 3,301,160 Patented Jan. 31, 1967 FIG. 2 is a frontelevational view of the assembled apparatus of FIG. 1.

As shown in FIG. 1, the tray structure comprises a rectangular container21 divided by parallel troughs 23 and 25. In the arrangement shown, byway of example,-

there are justitwo suchtroughs, but the number. may be increased tothree or more if desired. The container 21 carries a pair ofstructural'end plates 27 and 29. These are shaped and adapted to receiveand maintain, in proper operating position, a plurality ofrollers 31,33, and 35, respectively. For this purpose the plates 27 and 29 are eachprovided with suitable slots 37, 37', 39and 39',

respectively. These slots are adapted to receive the shafts of therollers 31, 33, and 35. Only one of these, the

shaft 41, is shown at the left of the roller 31.

. The intermediate roller 33, when assembled, normally rests upon theother two rollers and need not be actually Anyone of these rollersjournaled in the end plates. may be driven by suitable gear or otherdrive means, such as that indicated diagrammatically at 45. By ap plyingpower from a motor (not,'shown) to the drive 45, the roller 31 will bedriven and, due to the frictional contact with the other rollers, allwill be rotated. Thus, roller 33 may be driven by roller 31 and roller35 in turn by roller 33. Positive drive may be applied to one or moreadditional rollers, besides 31, if desired.

Immediately outside the end plates 27' and 29, respectively, are lateralliquid compartments indicated at 51 and 53. These are best seen inFIG. 1. At the right end of the tray, an additional liquid receivingcompartment 55 is shown which is adapted to receive the dispensing inletelement 57' of a suitable fluid supply unit. As

is adapted to contain a replenishable supply of liquid,

together with a simple means for assuring equal rates; of

a simple tray structure which includes conduit means for a directingand'dividing the liquid flow so as to first use up the stalest part ofthe liquid. i i i i A particular feature of the feed system includes theemployment of a gravity feeder connected toa single point formaintaining the predetermined operating level at all points in thesystem and with substantially equal freshness of the liquid supplied toall points.

Additional and subsidiary features are found in the interconnection ofthe troughs at each end whereby, by flowing fresh liquids into one endof each trough, both ends of both troughs are constantly supplied withfresh liquid and the fresh quality of the liquid is maintained at alltimes. d

Other objects and features will be apparent fromthe followingdescription of the invention, pointed out in particularity in theappended claims and taken in connection with the accompanying drawings,inwhich:

FIG. 1 is an exploded perspective view of a simple form of the apparatusincorporating the present invention; and

shown, a barometric or gravity-type feeding device 59 is provided, whichcomprises a supply tanlc61 and'the usual means for entrapping air sothat liquid willflow from the'device 57 only when it has receded to apredetermined level in the compartment 55. The assembled arrangement oftrayand feeder, plus the rollers is shown in FIG. 2. I I The liquidcompartments 53 and 55 at theright of FIG; 1 are each provided with anoverflow outlet pipe. These are indicated M63 and 65. These pipesproject up into the compartments to a predetermined operating levelwhere the liquid is to be maintained in the trough during developmentoperations. In other words the liquid will not ordinarily overflowthrough pipes 63 and 65 unless there is an accidental overfilling of thetray. The preferable arrangement is that the predetermined operatinglevel be just barely below the overflow level,-m'aking allowance for thesurface tension meniscus which forms at overflow.

Leading out'from the liquid receiving compartment'55 is a feed conduit71 which connects to-a distribution tank-73 placed about midpoint of thefront of the developer tray, and'is so positioned that separate streamsof liquid flow ing from there to the two end compartments 51, 53 willrequire a substantially equal time and will encounter approximately anequal frictional resistance in flow. The distribution tank 73 located atthe median point is'connected by conduits 75 and 77 to'the endcompartments 51 and 53, respectively. The pipes 75 and 77 areessentially of equ-al length" and equal diameter. With this arrangement,when liquid is supplied through conduit 71 to the median tank 73,assuming the apparatus is properly set at level, the flow rate of freshliquid through the-pipes 75 and77, will be substantially equal.

By theameans just describedthelateral compartments 51'and 53areconstantly kept full of fresh incoming liquid,

by gravity flow, up to the desired or predetermined operatpermi-tsliquid from lateral compartment 51 to flow through the interconnection81 into the left end of the rear trough 23, from which it may also flowindirectly through an interconnecting conduit 85 into the left end ofthe front tray. At the same time, liquid is supplied through pipe 77 tocompartment 53 from which it flows through the interconnection 83 intothe right end of the front'tray '77. This tray is connected by a conduit87 with the right end of the rear tray so that the liquid level inboth-ends"of both trays is maintained equal. The flow, is very simplycontrolled by gravity.

If desired, additional openings, as indicated in dotted lines at 81';83', may be provided to connect each of the,

end compartments to both ends of both trays. However, for equalizedflow, and to assure the active circulation or movement of liquidrequired to maintain a maximum of fresh developer solution at the pointor points of use, it is preferred to keep the flow channel under closecontrol at all times. Thisfavors the, method, as described, of bringingthe fresh fluid directly into only one end of one trough anddirectlyintothe other end of the other trough, with cross-communicationbeing established to supply the alternate ends indirectly. The length ofthe pipes 75, 77 preferably is properly adjusted to compensate for thetime required for liquid to move laterally through compartments 51, 53,and through conduits 81,

85 and 83, 87, respectively. ;Such means are employed to equalize theflow throughout the system.

In operation of the device, it will lie-understood that thesensitizedsheet material to be treated with the developer liquid ispassed under or between the rollers, thereby receiving the developerliquid by surface contact. Thus the level of the solution will graduallydecrease as the liquid is absorbed by the treated sheet materials As thelevel of liquid in the tray is lowered a small incremental distance bysuch depletion, the barometric feeder 57 allows a new supply of liquidto be introduced" in a suitably small quantity, usually in small amountsat frequent intervals, into the end supply compartment 55. From thisreceiving compartment it flows through the conduit means 71, 75, 77, asdescribed, and through the various other channels into the trays. Withthis arrangement, the circulation in both troughs23 and 25 is from theends toward the middle .where the, major consumption takes place. As thefluid is consumed, fresh fluid is constantly entering the system so thata substantially uniform freshnessis maintained throughout the fulllength of both trays. There are no substantialareas of non-flow, such ascorners or pockets, in which stale or spentfluid may accumulate.

It will be understood that the apparatus and the method of its operationare applicable to solutions other, than developer fluid, such as fixingsolutions and other treating liquids. The device may. be employed toapply various coating materials wherever it is important to maintain acertain or known degree of freshness with constant orsub'st'antiallyconstant replenishment of the material consumed- By meansof this apparatus, properly set on a level base, the fresh liquidmaterial is always introduced at both ends of all the troughs to flow,as shown, toward the center whereit is taken up and out of the system.No special mixing means are required to prevent accumulation of staleareas of liquid. Obviously, if, for any reason, the liquid is consumedfaster in any tray, or in any part of a tray, than in other trays or.tray." parts, the system will supply fresh liquid at the properreplenishment rate. j

What is claimed is:

1. A developer tray.v which comprises, in combination, a plurality ofelongated parallel troughs each adapted to contain a supply of developerliquid, a liquiddonduit means of approximately equal flow resistanceconnected to each end of each trough and leading to a single supplypoint, means for supplying liquid simultaneously to all.

said conduit means at said single point, and means for feeding liquidsupplied to the ends of said troughs directly into an end of one troughand indirectly into the corresponding end of another trough whilefeeding directly 1nt0 another end of the last mentioned trough andindirectly into the corresponding end of the first mentioned trough,

whereby. an essentially fresh liquid supply is continuously maintainedin all parts of all troughs by feeding fresh liquid into each end ofeach trough assaidliquid is consume-d.

2. In apparatus of the character described, the combination whichcomprises a tray structure including a pair of spaced parallel troughsadapted to hold liquid up to an operating level, a separate supplycompartment adjacent each end of said pair of troughs, conduit means forsimultaneously supplying liquid by gravity to both said compartments, aninterconnection between each of said compartments and each of saidtroughs, and liquid level maintaining means for supplyingliquid-to saidconduit means so as to maintain a predetermined operating liquid levelin both said troughs.

3. Combination according to claim 2 wherein the troughs are alsointerconnected for liquid flow between them.

4. Combination according to claim 2 wherein the troughs areinterconnected at both ends for liquid flow 7 between them.

5. Combination according to claim 2 wherein the troughs areinterconnected at both ends for liquid flow, and wherein fresh liquidflows directly into a first one of said troughs and indirectly into thesecond trough at one end and flows directly into the second trough andindirectly into the first trough at the other end.

6.-Combination according to claim 2 wherein a hard metric feeder isprovided to maintain by gravity feed the liquid level directly insaidconduit means and indirectly in said troughs.

7.. In apparatus of the character described, the combination whichcomprises a tray structure including a pair of parallel troughs eachadapted to contain a liquid up to a predetermined operating. level, endcompartments adjacent each end of said trough and interconnectedtherewith for liquid flow from said compartments to said troughs bygravity, a liquid receiving compartment, a supply conduit system whichincludes a median feed point and which also includes a first supplyconduit connected from said point to said liquid receiving compartmentand a pair of substantially equal length branch lines, one running fromsaid point to eachof said end compartments, whereby fresh liquid issupplied from said median point to either end of either trough atessentially the same .rate, thereby to substantially avoid differentialexhaustion of the liquid in said troughs.

8.1 Combination according to claim 7 wherein a baromatric gravitytfeeder is connected to said liquid receiving compartment to maintain asupply of liquid at said predetermined operating level.

9. Combination according to claim 7 wherein said troughsare'interconnected at both ends by free flowing liquid conduits toprevent differences in liquid level.

References Cited by the Examiner Limberger -8 9 NlORTON ANSHER, PrimaryExaminer. JOHN M. HORAN, Examiner.

C. B. PRICE, Assistant Examiner.

2. IN APPARATUS OF THE CHARACTER DESCRIBED, THE COMBINATION WHICHCOMPRISES A TRAY STRUCTURE INCLUDING A PAIR OF SPACED PARALLEL TROUGHSADAPTED TO HOLD LIQUID UP TO AN OPERATING LEVEL, A SEPARATE SUPPLYCOMPARTMENT ADJACENT EACH END OF SAID PAIR OF TROUGHS, CONDUIT MEANS FORSIMULTANEOUSLY SUPPLYING LIQUID BY GRAVITY TO BOTH SAID COMPARTMENTS, ANINTERCONNECTION BETWEEN EACH OF SAID COMPARTMENTS AND EACH OF SAIDTROUGHS, AND LIQUID LEVEL MAINTAINING MEANS FOR SUPPLYING LIQUID TO SAIDCONDUIT MEANS SO AS TO MAINTAIN A PREDETERMINED OPERATING LIQUID LEVELIN BOTH SAID TROUGHS.